C2022 E3 (ZTF)

Comet C/2022 E3 (ZTF)

Discovered by astronomers at the Zwicky Transient Facility (ZTF) on 2022, March 2, it is long period comet from the Oort Cloud. It reached perihelion on 2023, January 12, at a distance of 1.11 AU from the Sun and was closest to Earth (0.28 AU) on 2023, February 1.

In mid January, it first became visible to the naked eye from dark sky locations in the northern hemisphere and reached mag 5 when closest to Earth. During the last week of January a favourable comet-Earth-Sun alignment enabled an anti-tail (a tail apparently pointing towards the Sun) to become significant and splendid images can be found on-line. By the time of closest approach to Earth, it was moving rapidly southwards and by February 6 it had travelled sufficiently south to become visible low on the northern horizon to observers in southern Australia. Despite receding from both the Earth and the Sun as it moved southwards, it became a relatively easy photographic subject during the latter half of February.

	2023 February 08: photographed against the stars of Auriga when about magnitude 6, but low in altitude from southern Australia. Canon 5D II + 500mm lens, on an NEQ6 Pro mount tracking the sky. A series of thirty six 45 sec exposures (~27 mins total) at f5 and ISO 2500 were aligned on the comet, while eight of the images (6 mins total) were separately aligned on the stars. These were combined to optimise the comet against the star field; field of view 4.1° x 2.8°, north is to the right.
	2023 February 19: about magnitude 6 photographed against the stars of Taurus at a much more favourable altitude. Takahashi TOA-130, fl=1000mm, f7.7 + SBIG STL11000M camera on a Takahashi EM-200 Temma2 mount tracking the sky. A series of seven R:G:B filtered frames each 180 secs long were separately aligned on the comet and on the stars. These were combined to optimise the comet against the stars; field of view 2.1° x 1.4°, north is to the right.
	2023 February 20: about magnitude 6 photographed against the stars of Taurus. Takahashi TOA-130, fl=1000mm, f7.7 + SBIG STL11000M camera on a Takahashi EM-200 Temma2 mount tracking the sky. A series of seven R:G:B filtered frames each 180 secs long were separately aligned on the comet and on the stars. These were combined to optimise the comet against the stars; field of view 2.1° x 1.4°, north is to the right.